GB2188721A

GB2188721A - Roll temperature measurement

Info

Publication number: GB2188721A
Application number: GB08608337A
Authority: GB
Inventors: Andrew Ronald Spence; Peter Watson; Alexander Perkins
Original assignee: British Steel Corp
Current assignee: British Steel Corp
Priority date: 1986-04-04
Filing date: 1986-04-04
Publication date: 1987-10-07
Also published as: GB2188721B; GB8608337D0

Abstract

A device for measuring the temperature of supporting guide rolls in a continuous casting machine is mounted in a dummy bar mechanism 2, 3 for initiating the strand withdrawal and comprises temperature sensors 5 and 6 operative to measure the temperature of each roll as the dummy bar mechanism is transported between the said supporting rolls. Proximity switches 9 and 10 trigger the temperature sensors when they are adjacent a roll, and the relevant temperature and identity of each roll is stored in a microprocessor for interragation after removal from the machine. <IMAGE>

Description

SPECIFICATION Roll temperature measurement This invention relates to measuring the temperature of rolls, more particularly the supporting rolls in a continuous casting machine applicable to casting metal slabs, blooms or billets, eg steel.

In a continuous casting machine as the partially solidified strand is withdrawn from the mould it initially passes through a cooling chamber whilst being supported and guided by a series of rolls within this chamber.

Accessibility to these rolls is restricted and thus it is difficult to monitor the temperature of these rolls. Inadequate roll cooling can lead to permanent roll bending or cracking and, more importantly, it can lead to increased bending during casting which can impair the quality of the cast product and yet may not be detectable when the roll is cold.

It is an object of this invention to mitigate this problem.

In accordance with this invention there is provided a device for measuring the temperature of supporting guide rolls in a continuous casting machine, the device being mountable in a dummy bar mechanism for initiating the strand withdrawal and comprising temperature sensors operative to measure the temperature of each roll as the dummy bar mechanism is transported between the said supporting rolls.

The device is preferably mounted in the dummy bar linkage closely adjacent to the dummy bar head and the measurement is effected on insertion of the mechanism during restranding, that is immediately after the previous cast, this restranding operation may be effected with the mechanism either being fed downwardly through the mould or driven upwardly into position from below.

The information, which will identify the relevant roll together with its temperature, may be accessed remotely during the passage of this device between the relevant rolls or when the dummy bar head is in situ within the mould, or alternatively it may be accessed directly after casting has commenced and the dummy bar mechanism has been disconnected and parked. The device may conveniently be removed from the linkage at this juncture and the signals extracted and processed.

In accordance with this invention the temperature of most, if not all, of the supporting/guide rolls, which are in an inaccessible and harsh environment, can be measured in this fashion simply, reliably and systematically.

In order that the invention may be fully understood, one embodiment thereof will now be described, by way of example, with reference to the accompanying drawing in which: Figure 1 is a schematic side elevation of a dummy bar mechanism incorporating a device according to this invention mounted within supporting rolls, and Figure 2 is a plan view of the linkage illustrating the disposition of the device.

Referring to Fig. 1 there is illustrated a series of supporting rolls 1 in the upper end of a curved cooling chamber located beneath the mould in a continuous casting machine. A dummy bar mechanism comprising a dummy bar head 2 and a series of links 3, 4 is shown moving upwardly powered by a drive mechanism (not shown) to position the head within the mould. Mounted within the link 4 is the device according to this invention comprising two temperature sensors 5, 6 responsive to incident radiation from opposite rolls and 'tuned' to the appropriate temperature range, these sensor elements being shielded against moisture and dirt by sapphire windows 7, 8, respectively, that is, these 'windows' are transparent to the detected radiation but resistant to the environment.Two proximity switches 9, 10 are located on opposite sides of the sensors and a battery powered microprocessor 11 completes the assembly, the whole being mounted within a protective housing 12.

Fig. 2 shows the location of the device in more detail within the linkage.

In operation, during restranding the dummy bar linkage is driven upwardly along the curved path and the proximity switches trigger the temperature sensors such that they essentially respond only to the temperature of that roll adjacent which they are sited, and a counting algorithm is defined within the microprocessor 11 to identify each roll in turn. The relevant temperature measurements of all rolls traversed are thus stored within this microprocessor when the dummy bar reaches its extreme position within the mould.

The dummy bar mechanism is subsequently withdrawn as casting commences and after passage through the withdrawal and straightening rolls the mechanism is moved to its 'parked' position and the head is unlocked from the strand.

The housing 12 may then be removed from its location and the signals extracted and processed giving the requisite temperature of each roll. Any corrective or remedial action may then be effected before the next cast.

Although the invention has been described with reference to the specific embodiment illustrated it is to be understood that various modifications may readily be made without departing from the scope of this invention. For example the principle is applicable to either bottom fed (as shown) or top fed dummy bar mechanisms. Further, on a matter of detail, the temperature sensors may be protected by a window or cover other than sapphire.

1. A device for measuring the temperature of supporting guide rolls in a continuous casting machine, the device being mountable in a

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Roll temperature measurement This invention relates to measuring the temperature of rolls, more particularly the supporting rolls in a continuous casting machine applicable to casting metal slabs, blooms or billets, eg steel. In a continuous casting machine as the partially solidified strand is withdrawn from the mould it initially passes through a cooling chamber whilst being supported and guided by a series of rolls within this chamber. Accessibility to these rolls is restricted and thus it is difficult to monitor the temperature of these rolls. Inadequate roll cooling can lead to permanent roll bending or cracking and, more importantly, it can lead to increased bending during casting which can impair the quality of the cast product and yet may not be detectable when the roll is cold. It is an object of this invention to mitigate this problem. In accordance with this invention there is provided a device for measuring the temperature of supporting guide rolls in a continuous casting machine, the device being mountable in a dummy bar mechanism for initiating the strand withdrawal and comprising temperature sensors operative to measure the temperature of each roll as the dummy bar mechanism is transported between the said supporting rolls. The device is preferably mounted in the dummy bar linkage closely adjacent to the dummy bar head and the measurement is effected on insertion of the mechanism during restranding, that is immediately after the previous cast, this restranding operation may be effected with the mechanism either being fed downwardly through the mould or driven upwardly into position from below. The information, which will identify the relevant roll together with its temperature, may be accessed remotely during the passage of this device between the relevant rolls or when the dummy bar head is in situ within the mould, or alternatively it may be accessed directly after casting has commenced and the dummy bar mechanism has been disconnected and parked. The device may conveniently be removed from the linkage at this juncture and the signals extracted and processed. In accordance with this invention the temperature of most, if not all, of the supporting/guide rolls, which are in an inaccessible and harsh environment, can be measured in this fashion simply, reliably and systematically. In order that the invention may be fully understood, one embodiment thereof will now be described, by way of example, with reference to the accompanying drawing in which: Figure 1 is a schematic side elevation of a dummy bar mechanism incorporating a device according to this invention mounted within supporting rolls, and Figure 2 is a plan view of the linkage illustrating the disposition of the device. Referring to Fig. 1 there is illustrated a series of supporting rolls 1 in the upper end of a curved cooling chamber located beneath the mould in a continuous casting machine. A dummy bar mechanism comprising a dummy bar head 2 and a series of links 3, 4 is shown moving upwardly powered by a drive mechanism (not shown) to position the head within the mould. Mounted within the link 4 is the device according to this invention comprising two temperature sensors 5, 6 responsive to incident radiation from opposite rolls and 'tuned' to the appropriate temperature range, these sensor elements being shielded against moisture and dirt by sapphire windows 7, 8, respectively, that is, these 'windows' are transparent to the detected radiation but resistant to the environment.Two proximity switches 9, 10 are located on opposite sides of the sensors and a battery powered microprocessor 11 completes the assembly, the whole being mounted within a protective housing 12. Fig. 2 shows the location of the device in more detail within the linkage. In operation, during restranding the dummy bar linkage is driven upwardly along the curved path and the proximity switches trigger the temperature sensors such that they essentially respond only to the temperature of that roll adjacent which they are sited, and a counting algorithm is defined within the microprocessor 11 to identify each roll in turn. The relevant temperature measurements of all rolls traversed are thus stored within this microprocessor when the dummy bar reaches its extreme position within the mould. The dummy bar mechanism is subsequently withdrawn as casting commences and after passage through the withdrawal and straightening rolls the mechanism is moved to its 'parked' position and the head is unlocked from the strand. The housing 12 may then be removed from its location and the signals extracted and processed giving the requisite temperature of each roll. Any corrective or remedial action may then be effected before the next cast. Although the invention has been described with reference to the specific embodiment illustrated it is to be understood that various modifications may readily be made without departing from the scope of this invention. For example the principle is applicable to either bottom fed (as shown) or top fed dummy bar mechanisms. Further, on a matter of detail, the temperature sensors may be protected by a window or cover other than sapphire. CLAIMS

1. A device for measuring the temperature of supporting guide rolls in a continuous casting machine, the device being mountable in a dummy bar mechanism for initiating the strand withdrawal and comprising temperature sensors operative to measure the temperature of each roll as the dummy bar mechanism is transported between the said supporting rolls.

2. A device according to claim 1, mounted in the dummy bar linkage closely adjacent to the dummy bar head.

3. A device according to claim 1 or claim 2, wherein the temperature and the density of each roll sensed is stored for retrieval.

4. A device according to any one of claims 1 to 3, wherein the information is accessed remotely during the passage of said device between the rolls or as it lies in situ within the machine mould.

5. A device according to any one of claims 1 to 4, wherein the device is removable from the dummy bar mechanism to enable the information to be accessed.

6. A device according to any one of claims 1 to 5, wherein proximity switches are sited on opposite sides of the temperature sensors effective to trigger same when proximate the said rolls.

7. A device according to any one of claims 1 to 6, comprising two sensors directed towards opposing rolls and each lying within protective seals in said device.

8. A device for measuring the temperature of supporting guide rolls in a continuous casting machine, substantially as herein described with reference to the accompanying drawing.